Method of producing mixed tricycloalkylidene peroxides

ABSTRACT

Mixed cyclic trimeric peroxides are prepared by reacting 1,1&#39;&#39;dihydroperoxy dicyclic peroxides with cyclic ketones in liquid organic carboxylic acid solvents in the presence of strong acid catalysts at low temperatures. The mixed trimeric peroxides are converted to mixed dimeric peroxides by allowing an organic carboxylic acid solution thereof containing a strong acid catalyst to stand at about room temperature for a short period of time.

Story et al.

[ METHOD OF PRODUCING MIXED TRICYCLOALKYLIDENE PEROXIDES [75] Inventors:Paul Richard Story; Bunge Lee,

both of Athens, (3a.; Peter Busch, Willich, Germany [73] Assignee:Research Corporation, New York,

[22] Filed: May 15, 1972 [21] Appl. No.: 253,576

Related U.S. Application Data [63] Continuation-impart of Ser. No.842,689, July 17.

1969. abandoned.

[52] U.S. Cl. 260/338 [51] Int. Cl C07d 19/00 [58] Field of Search260/338 [56] References Cited UNITED STATES PATENTS 3.528.898 9/l970Story 260/338 Apr. 22, 1975 OTHER PUBLICATIONS T. Ledaal, Acta Chem.Scand., 21 (1967), No. 6. pp.

Houben-Weyl, Methoden der Organischen Chemie, Vol. VIII (1952). p. 56.

Primary E.\'aminerNorma S. Milestone Attorney, Agent, or Firm-Dennis P.Clarke; Harold L. Stowell [57] ABSTRACT Mixed cyclic trimeric peroxidesare prepared by reacting 1,1 '-dihydroperoxy dicyclic peroxides withcyclic ketones in liquid organic carboxylic acid solvents in thepresence of strong acid catalysts at low temperatures.

The mixed trimeric peroxides are converted to mixed dimeric peroxides byallowing an organic carboxylic acid solution thereof containing a strongacid catalyst to stand at about room temperature for a short period oftime.

7 Claims, No Drawings METHOD OF PRODUCING MIXED TRICYCLOALKYLIDENEPEROXIDES The work on which this application was based was financed inwhole or in part by the Department of Health, Education and Welfare.

RELATED APPLICATIONS This application is a continuation-in-part ofApplication Ser. No. 842,689, filed July 17, 1969 and now abandoned.

BACKGROUND OF THE INVENTION Macrocyclic hydrocarbons and lactones arevaluable compounds useful as odorants or intermediates for thepreparation of odorants in the perfume industry. They may be prepared bydecomposing the corresponding cyclic diand trimeric peroxides asdescribed in US. Pat. No. 3,528,898. Obviously, the odorantcharacteristic of the macrocyclic compound will depend in each instanceupon the ring size and the nature and location of the substituentsthereon.

Diand trimeric peroxides decompose to form macrocyclic compoundsaccording to the following reaction schemes:

Obviously, the ring size of the macrocyclic compounds will depend uponthe ring sizes of the starting peroxides. It will be readily apparentthat where the diand trimeric peroxides are symmetrical, i.e., x=y=z,their decomposition will yield macrocyclic compounds containing only 2xor 3x methylene (CH groups, respectively. Thus, the decomposition oftricyclopentylidene peroxide will yield cyclododecane andcyclotridecanolide; the decomposition of tricyclohexylidene peroxidewill yield cyclopentadecane and cyclohexadecanolide, etc. Likewise, thedecomposition of diheptylidene peroxide will yield cyclododecane andcyclotridecanolide, etc.

It will also be apparent that it would be impossible to producemacrocyclic compounds having 2x 2*: l or 3x i l methylene groups fromsymmetrical (xa =z) diand trimeric peroxides, respectively, since thedecomposition of each succeeding member of the symmetrical diandtrimeric peroxide families will yield macrocyclic hydrocarbons andlactones differing from the preceding group of products by the additionto the ring of 2 or 3 carbon atoms, respectively.

For example, it would be impossible to produce cyclotridecane from asymmetrical trimeric peroxide since tricyclopentylidene peroxide yieldscyclododecane and the next highest member of the series,tricyclohexylidene peroxide yields cyclopentadecane. Similarly, it wouldbe impossible to produce cyclotridecane from a symmetrical dimericperoxide since diheptylidene peroxide yields cyclododecane and the nexthighest member of the series, dioctylidene peroxide, yieldscyclotetradecane.

It will also be apparent that it would be impossible to producemacrocyclic hydrocarbons and lactones containing a single substituent orplural different substituents from symmetrical diand trimeric peroxides.Since in symmetrical peroxides each of the rings would contain the samesubstituent their decomposition would yield products containing 2 or 3identical substituents, depending upon whether the starting material isa dior trimeric peroxide.

The provision of non-symmetrical diand trimeric peroxides, i.e., thoseof the above structure wherein one or more of x, y and z are differentfrom each other, would enable the production of a wider variety ofmacrocyclic hydrocarbons and lactones having differing ring sizes andstructures. Moreover, the provision of non-symmetrical peroxidescontaining only a single substituent or a wide variety of substituentswould enable the production of substituted macrocyclic compoundsheretofore unavailable in an efficient and economical manner.

Thus, a cyclotridecane could be produced by decomposing dipentylidenecyclohexylidene peroxide, a mixed trimeric peroxide. Similarly,cyclotridecane could be produced from heptylideneoctylidene peroxide. Inaddition, methoxycyclotridecane and methoxycyclotetradecanolide could beproduced from dicyclopentylidene-4-methoxycyclohexylidene peroxide.

It should be readily apparent, therefore, that the provision of mixedtrimeric and dimeric peroxides affords the perfume industry a lessexpensive and wider selection of macrocyclic hydrocarbons and lactonesthan heretofore available.

It is known that mixed organic trimeric peroxides may be prepared byreacting dihydroperoxy dicycloalkyl peroxides with liquid ketones. Atpp. 5456 of Vol. 8 of Houben-Weyl, Methoden der Organischen Chemie(1952) there is disclosed a method for preparing isopropylidenedicyclohexylidene peroxide by treating l,- 1 -dihydroperoxydicyclohexylperoxide with an excess of acetone in the presence of anhydrous cupricsulfate for 14 days. The use of hydrochloric acid as a catalyst is alsodisclosed. This method is limited to the employment of liquid ketones,however. Heretofore, no method has been suggested which permits the useof solid ketones.

Additional prior art relating to the production of organic peroxidesincludes an article by T. Ledaal in Acta. Chem. Scand., Vol. 21, (1967)pp. 165657 wherein it is disclosed that symmetrical or non-mixed dimericperoxides may be prepared by treating a carboxylic acid solvent solutionof a ketone'hydroperoxide with a strong acid. When employingcyclopentanone hydroperoxide a non-mixed trimeric peroxide was produced.

Dilthey et al., in Vol. 154 of Jour. Prakt. Chem. (1939-40) at pp.2l9237 disclose the oxidation of various ketones to produce non-mixed orsymmetrical trimeric peroxides.

I-Ieretofore, however, there has existed no efficient method for theproduction of relatively high yields of mixed or non-symmetrical diortrimeric cyclic peroxides. a

It is an object, therefore, of the present invention to provide anefficient method for the production of mixed or non-symmetricaltricyelic peroxides.

It is a further object of the present invention to provide a method forthe preparation of mixed or nonsymmetrical dicyclic peroxides bydecomposition of the mixed trimeric peroxides.

It is a further object of the present invention to provide novel mixedor non-symmetrical diand tricyclic peroxides.

SUMMARY OF THE INVENTION It has been found that mixed cyclic trimericperoxides may be prepared in short reaction times in high yields byreacting a 1,1-dihydroperoxy dicyclic peroxide with a cyclic ketone in aliquid organic carboxylic acid solvent in the presence of a catalyticamount of a strong acid catalyst at low temperatures.

The resulting mixed trimeric peroxide may be converted to a mixeddimeric peroxide by allowing an organic carboxylic acid solution thereofcontaining a catalytic amount of a strong acid catalyst to stand atabout room temperature for a short period of time.

DETAILED DESCRIPTION OF THE INVENTION More specifically, it has beendiscovered that mixed tricyeloalkylidene peroxides in which at least oneof the three of the cyclic ketone precursor molecules are not of thesame structure, of the following general formula:

in which x, y and z are positive integers of from 4 to 17 may beprepared in high yields by treating a 1,1 dihydroperoxydicyclicperoxideof the following general formula:

OOH

in which x and y are positive integers of from 4 to 17 with a cyclicketone of the following general formula:

in which 1 is a positive interger of from 4 to 17 in a liquid organiccarboxylic acid wherein the ratio of peroxl ide to acid solvent is from50 mmoles of peroxide in ml of acid solvent to 50 mmoles of peroxide in3,000 ml of acid solvent, with the preferred ratio being 50 mmoles ofperoxide to 100 ml of acid solvent, in the presence of a strong mineralor organic acid catalyst; the ratio of peroxide to acid catalyst beingfrom 200 mmoles of peroxide to about 1 ml of concentrated acid to 200mmoles of peroxide in 100 ml of concentrated acid with the preferredratio being 200 mmoles of peroxide to ml of catalyst, at temperaturesranging from C to C with the preferred temperature being approximately20C. The thus produced mixed trimeric peroxide is obtained as a solidsimply by adding water or methanol to the above organic acid reactionsolution after a sufficient reaction time of from a few minutes toseveral hours with the preferred time being 5 hours. The pure trimer isthen obtained by washing the solid with water.

It is a further feature of the present invention that the mixedtricyclic peroxides of the present invention may be converted into mixeddicyclic peroxides which are new compositions of matter. The tricyclicperoxides are converted into excellent yields of the correspondingdicyclic peroxides by allowing a solution of the tricyclic peroxide inacetic acid or in propionic acid or a mixture of the two acids, and amineral acid such as perchloric acid to stand at a temperature of fromabout 0C to about 50C, preferably about room temperature for shortperiods of time of from a few minutes to 24 hours. Alternatively, thetrimeric peroxides may be converted into the dimeric peroxide by heatingthe reaction mixture in which they are produced to the abovetemperature. Generally, the same reactant, carboxylic acid solvent andcatalyst proportions set forth above for production of the mixedtrimeric peroxides may also be employed in preparing the dimericperoxides. These mixed dicycloalkylidene peroxides decompose to givemixtures of macrocyclic compounds which are most useful in the perfumeindustry as odorants, for example, cyclononones and cycloundecanes.Substituted dicyclic peroxides containing the above-mentionedsubstituents may also be prepared according to the method of theinvention.

The preparation of these mixed dicycloalkylidene peroxides isillustrated as follows:

C (I) 0 (K m m m/0 O\C/\ C (en (ca 2 a A X 2 y o o V (x.z)

Suitable liquid organic carboxylic acid solvents include the liquid,lower aliphatic, preferably lower alkanoic acids such as acetic, formic,propionic and butyric acids.

A wide variety of strong acid catalysts may be employed, such asperchloric, para toluene sulfonic, hydrochloric sulfuric and nitricacids.

While the above structural formulae do not include substitutedperoxides, the method of the invention is also applicable to thepreparation of various substituted mixed tricycloalkylidene peroxides.They may be substituted with the following groups: lower alkyl, hydroxy,lower alkoxy, carboxy, hydroxyloweralkyl, carboxyaryl,carboxyloweralkyl, etc. These peroxides produced by the method of thepresent invention are useful for the synthesis of macrocyclic compoundsas described in US. Pat. No. 3,528,898. Obviously, the production ofthese types of macrocyclic compounds would be impossible utilizingsymmetrically substituted peroxides.

in which x is a positive integer of from 4 to 17 and y is a positiveinteger of from 4 to 17. Not only does this process yield mixeddicycloalkylidene peroxides but also non-mixed dicycloalkylideneperoxides.

EXAMPLE I A solution of 5 mmoles of cyclopentanone in 10 ml of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below 20C by adding dry ice to thesolution. To this cooled solution was added with stirring 0.5 ml ofaperchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained atabout 20C for 1 hour after addition was completed. The temperature wasthen raised to 0C and kept there for 4 hours. At this time about 35 mlof water was added, resulting in separation of crystals. The separatedproduct was washed with water and dried giving 1.09 gramsof'tricyclopentylidene peroxide, a 73% yield. The peroxide product wasidentified by infrared comparison, elemental analysis and by the natureof the products obtained on thermal decomposition of the peroxide,producing a macrocyclic compound.

EXAMPLE 11 A solution of 5 mmoles cyclohexanone and 10 ml of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below 20C by adding dry ice to thesolution. To the cooled solution was added with stirring 0.5 ml of aperchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained atabout 20C for 1 hour after addition was complete. The temperature wasthen raised to C and kept there for 4 hours. After this time, 35 ml ofwater was added, resulting in a separation of crystals. The crystalswere washed and dried, giving a yield of 0.99 grams ofdicyclopentylidene cyclohexylidene peroxide, a yield of 63%.

EXAMPLE Ill A solution of 5 mmoles of cycloheptanone in ml of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below C by adding dry ice to thesolution. To the cooled solution was added with stirring 0.5 ml ofaperchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained at20C for one hour after addition was complete. The temperature was thenraised to 0 C and kept there for 4 hours. After this time, about 35 mlof water was added which resulted in separation of crystals. Thecrystals were washed with water and dried. The resulting product wasdicyclopentylidenecycloheptylidene peroxide in the amount of 0.61 grams,a yield of 37%. The product was identified as in Example I.

EXAMPLE IV A solution of 5 mmoles of cyclopentanone in 10 ml ofpropionic acid was placed in a 50 ml Erlenmeyer flask containing aspinbar for magnetic stirring and cooled tojust below 20 C by adding dryice to the solution. To the cooled solution was added with stirring 0.5ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of1,1 dihydroperoxydicyclohexyl peroxide. The temperature was maintainedat about 20 C for one hour after addition was complete. The temperaturewas then raised to 0 C and kept there for 4 hours. After this time, 35ml of water was added resulting in a separation of crystals. Thecrystals were washed and dried. The produce wasdicyclohexylidenecyclopentylidene peroxide in the amount of 1.02 grams,a yield of 62%. The product was identified as in Example 1.

EXAMPLE V A solution of 5 mmoles of cyclohexanone and 10 ml of propionicacid was placed in a 50 ml Erlenmeyer and 5 mmoles of 1,1dihydroperoxydicyelohexyl per- I oxide. The temperature was maintainedat about 20 C for 1 hour after addition was complete. The temperaturewas then raised to 0 C and kept there for 4 hours.

After this time, 35 ml of water was added resulting in crystalseparation. The crystals were washed and dried. The product thusproduced was tricyclohexylidene peroxide in the amount of 1.30 grams, ayield of 76%. The product was identified as in Example 1.

EXAMPLE VI A solution of 5 mmoles of cyclopentanone in 10 ml ofpropionic acid was placed in a 50 ml Erlenmeyer flask containing aspinbar for magnetic stirring and cooled to just below 20 C by addingdry ice to the solution. To the cooled solution was added with stirring0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmolesof l,l-d1hydroperoxydicycloheptyl peroxide. The temperature wasmaintained at about 20 C for one hour after addition was complete. Thetemperature was then raised to 0 C and kept there for 4 hours. Afterthis time, 35 ml of water was added resulting in crystal separation. Thecrystals were washed with water and dried. The product wasdicycloheptylidenecyclopentylidene peroxide, 1.17 grams, a yield of 66%.The product was identified as in Example 1.

EXAMPLE V11 A solution of 50 mmoles of 4-methoxycyclohexanone and 20 mlof propionic was cooled down to 20 C by adding powdered dry ice. Thesolution was stirred and to it was added 02ml of 10% perchloric acid inacetic acid and 5 mmoles of l,1dihydroperoxydicyclododecyl peroxide. Thetemperature of the solution was maintained at 20 C for 1 V2 hours andthen raised to 0 C and maintained at this temperature for 2 /2 hours.Water was added to the reaction mixture which yielded 2 grams of acolorless mass. After filtering, the mass turned pasty and it wasstirred in methanol for 4 hours at 0 C which yielded a colorlesscrystalline product, dicyclododecyclidene-4-methoxycyclohexylideneperoxide, identified by infrared analysis.

EXAMPLE V111 A solution of 5 mmoles of 4-methoxycyclohexanone in 20 mlof propionic acid was placed in a ml Erlenmeyer flask containing .aspinbar for magnetic stirring and cooled to just below 20 C by addingpowdered dry ice to the solution. To this solution was added 0.5 ml of10% perchloric acid in acetic acid and 10 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained atabout 20C for 2 hours after addition was completed. The temperature wasthen raised to about 0C and after 2 more hours, 100 ml of water wasadded to the reaction mixture, resulting in a heavy oil. This oil becamea pasty mass by stirring with a large amount of water for several hoursat 0C. The water was decanted and the reaction product dried. Thisproduct was dicyclopentylidene-4-methoxycyclohexylidene peroxide asidentified by infrared analysis.

A 500 mg sample of the dicyclopentylidene-4- methoxycyclohexylideneperoxide was thermolyzed by refluxing in 10 ml decane for 2 hours. Gaschromatographical analysis of the reaction mixture which was identifiedby infrared analysis disclosed the decomposition products to bemethoxycyclotridecane; 20% yield; methoxycyclotetradecanolide,approximately 20% yield; and the methoxy derivative of a cyclicdilactone containing 15 C. atoms.

The following examples are directed to the synthesis of mixeddicycloalkylidene peroxides from mixed tricycloalkylidcne peroxides.

EXAMPLE IX A solution 5 mmoles of cyclohexanone in 10 ml of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below 20C by adding dry ice to thesolution. To the cooled solution was added with stirring 0.5 ml of aperchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained atabout 20 C for 1 hour after addition was complete. At this point, thetrimeric mixed peroxide, dicyclopentylidenecyclohexylidene peroxide wasproduced.

After maintaining the solution for one hour at -20 C, the temperaturewas raised to C and kept there for 4 hours. Thereupon, 25 ml of aceticacid and 1 ml of the perchloric acid solution, all at room temperature,were added to the reaction mixture with stirring. After 1 hour at roomtemperature, the mixture was diluted with about 100 ml of water. Thecrystalline solid which separated was filtered and washed with water andthen recrystalized with acetone-water. A mixed dicycloperoxide wasproduced, cyclopentylidenecyclohexylidene peroxide and a non-mixedperoxide, dicyclohexylidene. The melting point of the mixeddicycloalkylidene peroxide was 78 105 and weighed 0.29 grams which gavea yield of 27%. These products were established by their photolysis inmethylene chloride solvent which gave the corresponding macrocyclichydrocarbon whose structures were determined by infrared analysis andmass spectral analysis.

EXAMPLE X A solution of 5 mmoles of cycloheptanone in ml of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below C by adding dry ice to thesolution. To the cooled solution was added with stirring 0.5 ml of aperchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclopentyl peroxide. The temperature was maintained atabout 20 C for 1 hour after the addition was completed. At this point, amixed peroxide was present, dicyclopentylidenecycloheptylidene.

Thereupon, ml of acetic acid and 1 ml of the perchloric acid solution,all at room temperature, was added to the reaction mixture withstirring. After 1 hour at room temperature, the mixture was diluted withabout 100 ml of water. The crystalline solid which separated wasfiltered and washed with water and then recrystalized withacetone-water. The products thus produced werecyclopentylidenecycloheptylidene peroxide, a mixed dicycloalkylideneperoxide, melting point 49 55 C. in the amount of 0.29 gramsrepresenting a yield of 27%, and dicycloheptylidene peroxide. Thesecompounds were identified as in Example IX.

EXAMPLE XI A solution of 5 mmoles of cyclopentanone in 10 ml ofpropionic acid was placed in a 50 ml Erlenmeyer flask containing aspinbar for magnetic stirring and cooled to just below -20 C by addingdry ice to the solution. To the cooled solution was added by stirring0.5 ml ofa perchloric acid solution, 10% in acetic acid, and

5 mmoles of 1,1 dihydroperoxydicyclohexyl peroxide. The temperature wasmaintained at about -20 C for 1 hour after addition was complete.

A mixed tricycloalkylidene peroxide was produced,dicyclohexylidenecyclopentylidene. Thereupon, 25 ml of acetic acid and 1ml of the perchloric acid solution, all at room temperature, was addedto the reaction mixture with stirring. After 1 hour at room temperature,the mixture was diluted with about 100 ml of water. The crystallinesolid which separated, was filtered and washed with water andrecrystalized with acetonewater. The products produced arecyclopentylidenecyclohexylidene peroxide, a mixed dicycloalkylideneperoxide with a melting point of between 120 C, 0.66 grams representinga yield of 62%, and dicyclohexylidene. The products were identified asin Example 1X.

EXAMPLE XII A solution of 5 mmoles of cycloheptanone in 10 of propionicacid was placed in a 50 ml Erlenmeyer flask containing a spinbar formagnetic stirring and cooled to just below 20 C by adding dry ice to thesolution. To the cooled solution was added with stirring 0.5 ml of aperchloric acid solution, 10% in acetic acid, and 5 mmoles of1,1dihydroperoxydicyclohexyl peroxide. The temperature was maintained atabout -20 C for 1 hour after addition was complete.

After this time, the temperature was raised to 0 C and kept there for 4hours. Thereupon 5 ml of acetic acid and 1 ml of the perchloric acidsolution, all at room temperature was added to the reaction mixture withstirring. After l hour at room temperature the mixture was diluted withabout ml of water. The crystalline solid which separated was filteredand washed with water and then recrystalized with acetonewater. Theproducts produced in this reaction were cyclohexylidenecycloheptylideneperoxide, a mixed dicycloalkylidcne peroxide with a melting point ofbetween 90 C, 0.90 grams, a yield of 84%, dicyclohexylidene peroxide anddicycloheptylidene peroxide. These products were identified as inExample IX.

EXAMPLE XIII The exact procedure of Example IX was followed exceptcyclopentanone was used and the peroxide 1,1dihydropcroxydicycloheptylwas used. This gave reaction products ofcyclopentylidenecycloheptylidene peroxide, a mixed dicycloalkylideneperoxide with a melting point of between 60 90 C, 0.53 gramsrepresenting a yield of 50%, and dicycloheptylidene peroxide.

EXAMPLE XIV The exact procedure of Example IX was used except1,1'dihydroperoxydicycloheptyl peroxide was used. The reaction productswere cyclohexylidenecycloheptylidene peroxide, a mixed dicycloalkylideneperoxide with a melting point of between 82 84 C, 0.79 grams, a yield of74%, dicyclohexylidene peroxide and dicycloheptylidene peroxide.

EXAMPLE XV The exact procedure of Example IX was followed exceptcyclooctanone ketone was used, and 1,1dihydroperoxydicycloheptylperoxide was used. The reaction products werecycloheptylidenecyclooctylidene peroxide, a mixed dicycloalkylideneperoxide with a melting point of between 82 91 C, 0.53 gramsrepresenting a yield of 50%, and dicycloheptylidene peroxide.

EXAMPLE XVI The exact prodedure of Example IX was used except1,1dihydroperoxydicyclohexyl peroxide was used. The reaction productswere dicyclohexylidene peroxide which had a melting point of between 125129 C, 1.03 grams representing a 97% yield.

The exact procedure of Example [X was used except cyclopentanone ketonewas used. The reaction products were dicyclopentylidene peroxide with amelting point of between 94l04 C, 0.055 grams representing a yield of5%.

EXAMPLE XVlll A solution of 5 mmoles of cyclododecanone in 10 ml ofpropionic acid was placed in a 50 ml Erlenmeyer flask containing aspinbar for magnetic stirring and cooled to approximately 20 C by addingdry ice to the solution. To the cooled solution was added with stirring0.5 ml of 10% perchloric acid in acetic acid and 5 mmoles ofl,ldihydroperoxydicyeloheptyl peroxide. The temperature was raised to Cand kept there for 4 hours. Thereupon 35 ml of water was added resultingEXAMPLE XlX A solution of 30.4 mmoles, 3.78 grams, of freshly distilledcyclooctanone and 30 ml of acetonitrile was prepared. To this solution 2ml of 98% hydrogen peroxide was added and the mixture was stirred forminutes at 0C, and then 5 drops of 70% perchloric acid were added. After24 hours stirring at 0C, there was obtained a very viscous liquid whichwas treated with 30 ml of methanol. The reaction solution was allowed tostand for 24 hours at 0C, yielding 870 mg of tricyclooctylideneperoxide, 20% yield of colorless crystals, m.p. 72C75C.

A solution of 400 mg of tricyclooctylidene peroxide was refluxed in mlof decane for 3 hours. A gas chromatograph analysis showed three peakswhose retention times matched with the expected thermal decompositionproducts of the above trimer.

EXAMPLE XX A solution of 5 mmoles of cyclohexane-1,4-dione in 30 ml ofpropionic acid was placed in a 100 ml Erlenmeyer flask containing aspinbar for magnetic stirring and cooled to just below C by addingpowdered dry ice to the solution. To the cooled solution was added withstirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and20 mmoles of 1,1 dihydroperoxydicyclohexyl peroxide. The temperature wasmaintained at 20C for 3 hours and then raised to 0C and maintained for17 hours. Thereupon, ml of water was added which resulted in theformation of a viscous liquid as the bottom layer. The bottom layer wasseparated and washed with water and then dissolved in about 20 ml ofmethanol. The solution was kept for 7 days at 0C, after this timecrystals separated; they were filtered, washed with methanol,recrystallized from acetone to give a yield of 0.48 grams, 13 per centyield, mp. C. The product, tetracyclohexylidene -l,4-cyclohexylidene,was checked by elemental analysis. molecular weight determination inbenzene and by infrared spectrum.

Thus, with the process of the present invention one is able to producemixed tricycloalkylidene peroxides in high yields as well as the mixeddicycloalkylidene peroxides in high yields within a short reaction timeemploying solid ketones. Also, it was not necessary to employ an excessof the ketones. The procedure itself is straight-forward and notcomplicated. Further, the process of this invention has produced noveldimeric peroxides.

What is claimed is:

l. A method for preparing nonsymmetrical trimeric peroxides of theformula:

lZ X C O 0 0 l (Cl-l K V C x R (C 2) wherein:

x and y are different and are positive integers of from 4 to 17 R ishydrogen or methoxy which comprises reacting 1,1-dihydroperoxydicyclicperoxide of the formula:

C (i) OOH d OOH (CH )x with a cyclic ketone of the formula:

2. The method of claim 1 wherein R is hydrogen.

3. The method of claim 1 wherein the strong acid catalyst is selectedfrom the group consisting of perchloric, hydrochloric, sulfuric, nitricand p-toluene sulfonic acids.

4. The method of claim 1 wherein the temperature is about -20C.

5. The method of claim 1 wherein the ratio of peroxide to concentratedacid catalyst is from about 200 mmolezml to about 200 mm0le:lOO/ml.

6. The method of claim 1 wherein the ratio of peroxide to acid solventis from about 50 mmolezlO ml to about 50 mmolez3000 ml.

7. The method of claim 1 wherein the acid solvent is propionic acid.

1. A METHOD FOR PREPARING NONSYMMETRICAL TRIMERIC PEROXIDES OF THEFORMULA:
 1. A method for preparing nonsymmetrical trimeric peroxides ofthe formula:
 2. The method of claim 1 wherein R is hydrogen.
 3. Themethod of claim 1 wherein the strong acid catalyst is selected from thegroup consisting of perchloric, hydrochloric, sulfuric, nitric andp-toluene sulfonic acids.
 4. The method of claim 1 wherein thetemperature is about -20*C.
 5. The method of claim 1 wherein the ratioof peroxide to concentrated acid catalyst is from about 200 mmole:ml toabout 200 mmole:100/ml.
 6. The method of claim 1 wherein the ratio ofperoxide to acid solvent is from about 50 mmole:10 ml to about 50mmole:3000 ml.